Mysterious wave of antelope deaths spark international inquest

Mysterious wave of antelope deaths spark international inquest

Nearly half of the world's critically endangered Saiga antelope have died suddenly in Kazakhstan since May.

Mysterious wave of antelope deaths spark international inquest

The Saiga antelope is a species of animal found on the central Asian steppes of Kazakhstan. Over time, the animal has adapted to the harsh and unrelenting temperatures of the extreme environment.

Following the fall of the Soviet Union, hunting and other environmental factors contributed to the species becoming critically endangered after reaching a low of 50,000.

Now, the species is facing a new threat. As of May 10, an unknown environmental trigger is thought to have been responsible for turning normally benign bacteria, present in the antelopes’ gut, deadly.

Once infected by the bacteria, the animals will die within hours of showing symptoms – which are depression, diarrhoea and frothing at the mouth.

Professor Richard Kock, from the Royal Veterinary College in London spoke to the BBC’s Science in Action programme, about his initial findings.

“They get into respiratory problems, they can’t breathe easily. They stop eating and are extremely depressed; the mothers die and then the calves are very distressed and then they die maybe one or two days later.”

The large numbers of Saiga found dead have been a huge set back for conservationists who have, up until this point, been making real progress in ensuring the survival of the endangered species.

Steffen Zuther, head of the Association for the Conservation of Biodiversity in Kazakhstan, was in charge of monitoring calving in one of the affected herds.

“Over two days (in the herd I was studying) 80% of the calving population died, the whole herd then died within two weeks.”

Overall, around 120,000 antelope have died – nearly half of the global population.

“What we’re seeing is sort of a perfect storm of different factors,” Prof Kock explained.

SERGEI KHOMENKO

In nearly every dead animal studied, two different bacteria, pasteurellosis and clostridia, have been found. Whilst these are found naturally in the respiratory and gut systems, their makeup has seemingly turned toxic.

Scientists have stated that the sudden transformation may be due to changes in climate triggering a dormant vulnerability.

“There’s no infectious disease that can work like this,” said Professor Kock. “This die-off syndrome has occurred on a number of occasions.”

None of these occurrences however, were anywhere near a match for the numbers seen this year.

Whilst the species is particularly resilient and adaptable to population loss, the extreme nature of this type of mass-death doesn’t make any sense to scientists.

“In a very severe winter..you could lose 90% of the population… but losing 100% of some populations within two weeks doesn’t make any sense from a biological or evolutionary perspective.” Professor Kock told the BBC.

Scientists have returned to the field and will continue to monitor the remaining herds in order to better understand the phenomenon and end it before it strikes again.